package shili;

public interface NewsDao {
    // 示例4(2)
    public static NewsDao getInstance(String key){
        switch (key){
            case "mysql":
                return new NewsDaoMySqlImpl();
            case "oracle":
                return new NewsDaoOracleImpl();
            case "redis":
                return new NewsDaoRedisImpl();
            default:
                throw new RuntimeException("无效的数据库类型:" + key + ",DAO获取失败");
        }
    }
}
